agreement vs hitting it off

agreement

noun
  • Rules that exist in many languages that force some parts of a sentence to be used or inflected differently depending on certain attributes of other parts. 

  • A legally binding contract enforceable in a court of law. 

  • An understanding between entities to follow a specific course of conduct. 

  • A state whereby several parties share a view or opinion; the state of not contradicting one another. 

hitting it off

How often have the words agreement and hitting it off occurred in a corpus of books? (source: Google Ngram Viewer )